Developer Disaster Drawer

If you want to get the real params (not actual url) you don’t have to pass it to the function.

function getValue(varname,url)
{
  // First, we load the URL into a variable  
  if (url == undefined) var url = window.location.href;

  // Next, split the url by the ?
  var qparts = url.split("?");

  // Check that there is a querystring, return "" if not
  if (qparts.length == 0)
  {
    return "";
  }

  // Then find the querystring, everything after the ?
  var query = qparts[1];

  if (query != undefined){
    // Split the query string into variables (separates by &s)
    var vars = query.split("&");

    // Initialize the value with "" as default
    var value = "";

    // Iterate through vars, checking each one for varname
    for (i=0; ivars.length; i++)
    {
      // Split the variable by =, which splits name and value
      var parts = vars[i].split("=");
      // Check if the correct variable
      if (parts[0] == varname)
      {
        // Load value into variable
        value = parts[1];

        // End the loop
        break;
      }
    }

    // Convert escape code
    value = unescape(value);

    // Convert "+"s to " "s
    value.replace(/\+/g," ");

    // Return the value
    return value;
  }
  return "";

}